But what are you going to run on the VM's as applications.
Your machine is very powerful
Say 2 cores per VM and 4 for the host.
That would give you 6-8 VM's with 1-2GB mem and 4gGB mem for the host.
But you will need a more robust and safer storage solution.
RAID 10 with at least 4 drives for the VM's
Put your swap partition there also, as you may not be swapping much and the SSD can be used for high writes files like log's.
Personally, I think you need a real scsi storge system with RAID 6 and 11-15 drives.